Digital camera and printing system

ABSTRACT

With a digital camera  100 , a photographed image  31  is displayed on a liquid crystal display and the user selects a desired image and specifies print specifications of the number of print sheets, a print paper size, a print color mode, etc., then print image data is prepared. The prepared print image data is transmitted from the digital camera  100  to a color printer of an output unit. An image is printed at the color printer in accordance with the print image data.

This is a continuation of application Ser. No. 09/081,786 filed May 20,1998 now U.S. Pat. No. 6,618,533; the disclosure of which isincorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a digital camera and in particular to adigital camera capable of outputting image data directly to a printerand a printing system using the same.

2. Related Art

In recent years, digital cameras (still-video cameras) have beendeveloped, sold, and finding spreading use.

The digital camera is configured to execute photoelectric conversion ofimage pickup light to provide image data, record the image data on arecording medium, and output the recorded image data to an externalimage processing system such as a personal computer (PC). The externalimage processing system performs print image data preparation processingand outputs the prepared print image data to a printer for printing orreproducing the picked-up image on paper.

Most digital cameras comprise each a liquid crystal display fordisplaying the image pickup result and the image data provided byphotoelectric conversion is compressed and recorded on a recordingmedium. To compress the image data, normally JPEG (Joint PhotographicExpert Group) standard is applied.

To select an image on a PC, a number of thumbnail images compressed inJPEG (described later) are previously input and displayed on a monitor.The picked-up image data corresponding to a selected thumbnail image isinput from the digital camera and is decompressed, then displayed on themonitor. When the user recognizes it, color print image data preparationprocessing is performed and the image is printed at a printer connectedto the PC.

The thumbnail image is a reduced image used for the user to select adesired image out of the input image data on a PC, etc. For example,assuming that the size of 1-frame image data is 680×480 pixels, thecorresponding thumbnail image is reduced by thinning out the data toabout 80×60 pixels; the thumbnail images are recorded on a recordingmedium of the digital camera in a one-to-one correspondence with normalpicked-up images.

When color print image data preparation processing is performed, printimage data preparation processing is performed by programs on the PC toreproduce or print a color image (video) with high accuracy and bit mapdata is prepared for each print color required for drawing and is givento a printer together with a control signal for performing the colorimage reproduction operation on recording paper.

A color print ink jet printer capable of printing a high-quality imagelike a picture or a photo is developed and sold as a color printer.

The above-mentioned print image data preparation processing programs arecontained in a program group called a printer driver in a dataprocessing module 210 as shown in FIG. 11. A printer driver 220 normallycomprises three modules of rasterizer, color correction, and halftone asmeans for obtaining binary data.

However, usually the PC comprises a large number of application programsother than image (video) print processing because of generalversatility. The application programs and the above-mentioned printerdriver operate under the control of Windows, MS-DOS, etc., (PC operatingsystem (OS) manufactured by Microsoft Corporation).

Therefore, to perform image print processing, the user needs to entercommands as specified by the OS for reading the print processingapplication program and the printer driver into PC internal memory froma storage unit storing them (for example, magnetic disk) and placingthem in an executable state. However, it takes time (so-called overheadtime) to enter commands and read the print processing applicationprogram and the printer driver; the overhead time requires severalminutes at the shortest, thus it takes time to start.

Although PCs are finding remarkable spreading use, many problems remainto be solved for users to know how to actually handle PCs; it is alsopointed out that most persons who have PCs cannot master them. If theyattempt to install the image (video) print processing applicationprogram and the printer driver, they may find it difficult to installthe software or may not understand how to enter the commands.

The need for using an expensive PC only for the purpose of printingpicked-up images involves remarkable impairment of user's convenience.

Examining demands for simplifying the print processing operation andreducing the overhead time almost to zero from the aspect of the digitalcamera, preferably, for example, image data can be output from thedigital camera directly to a printer without intervention of a PC and adesired picked-up image can be printed on a desired number of printsheets in a desired paper size and print color mode. More preferably, anexternal unit to which image data is to be transmitted including aprinter can be specified.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide a digital camerahaving capabilities of outputting image data directly to an externalsystem and printing a desired image under desired print specificationsof the number of print sheets, paper size, print color mode, etc. It isanother object of the invention to provide a printing system using thedigital camera.

According to one aspect of the invention, there is provided a digitalcamera for executing photoelectric conversion of image pickup light andthen recording the conversion result as image data, the digital cameracomprising a display section for displaying an image, a recording mediumfor recording the image data, image data selection means for selectingdesired image data out of the recording medium, and output methodspecification means for outputting the selected image data to anexternal system under predetermined output specifications. The imagedata selection means reads the image data for each frame and adds anindex to the image data for display on the display section.

According to another aspect of the invention, there is provided adigital camera for executing photoelectric conversion of image pickuplight and then recording the conversion result as image data andthumbnail image data of the image data, the digital camera comprising adisplay section for displaying an image, a recording medium forrecording the image data and the thumbnail image data, thumbnail imagedisplay means for reading the thumbnail image data from the recordingmedium and displaying thumbnail images on the display section, imagedata selection means for selecting one of the displayed thumbnailimages, thereby selecting desired image data corresponding thereto, andoutput method specification means for outputting the selected image datato an external system under predetermined output specifications. Thethumbnail image display means enlarges and displays the thumbnail image.

According to another aspect of the invention, there is provided adigital camera for executing photoelectric conversion of image pickuplight and then recording the conversion result as image data andthumbnail image data of the image data, the digital camera comprising adisplay section for displaying an image, a recording medium forrecording the image data and the thumbnail image data, thumbnail imageprint means for printing out the thumbnail image data recorded on therecording medium at an external printer, thumbnail image display meansfor reading the thumbnail image data from the recording medium anddisplaying thumbnail images on the display section, image data selectionmeans for selecting one of the displayed thumbnail images based on theprinted thumbnail images, thereby selecting desired image datacorresponding thereto, and output method specification means foroutputting the selected image data to an external system underpredetermined output specifications. The thumbnail image print meansadds an index to each thumbnail image data piece and outputs to theexternal printer and the index of one of the indexed thumbnail imagesprinted is specified, whereby the image data selection means selectsdesired image data corresponding thereto.

With the digital cameras according to the three aspects of theinvention, the external system is a color printer and the predeterminedoutput specifications contain at least one of the number of printcopies, a print paper size, and a print color mode for printing theimage data. The print color mode is full color, single color, ormonochrome. The external system contains a printer or a facsimile or animage processing system connected by a communication line.

A printing system provided according to the invention comprises any ofthe three types of digital cameras described above and a color printeras an external system.

BRIEF DESCRIPTION OF THE DRAWINGS

In the accompanying drawings:

FIGS. 1( a)-1(b) are block diagrams to show a configuration example of adigital camera of the invention;

FIG. 2 is a block diagram to show a configuration example of controlmeans stored in ROM;

FIGS. 3( a)-3(d) are block diagrams to show a configuration example ofimage selection means;

FIG. 4 is a block diagram to show the relationship among image selectionmeans, print image data preparation programs, and control means;

FIG. 5 is a flowchart to show brief operation of a control section;

FIG. 6 is a block diagram to show a configuration example of outputmethod specification means;

FIGS. 7( a)-7(b) are examples of a rear part view of the digital camera:

FIG. 8 is a flowchart to show an operation example from image selectionto print image data preparation;

FIG. 9 is a flowchart to show another operation example from imageselection to print image data preparation;

FIG. 10 is a flowchart to show another operation example from imageselection to print image data preparation; and

FIG. 11 is a block diagram to show an example of print image datapreparation programs used to prepare print data on a personal computer.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 is a block diagram to show a configuration example of a digitalcamera of the invention.

As shown in FIG. 1 a, a digital camera 100 comprises an optical systemconsisting of a lens, an iris mechanism, etc., through which reflectedlight from an image to be photographed is incident on a CCD 2, the CCD 2for converting image pickup light from the optical system 1 into anelectric signal, a signal processing section 3 for processing the signalfrom the CCD 2 and outputting the processed signal to a frame memory 6as multiple-valued (R, G, B) raster data (image data), a control section4 for controlling the operation of the signal processing section 3,frame memories 6 and 6′, a signal processing section 7, and a recordingmedium control section 8, image processing, imagecompression/decompression processing, etc., input means 5 for inputtinga command entered by the user operating a switch, etc., converting thecommand into a digital signal, and feeding the digital signal into thecontrol section 4, the signal processing section 7 for converting R, G,B raster data in the frame memory into brightness component Y and colordifference components U and V, compressing the data in JPEG, andperforming reduction processing for preparing a thumbnail image, arecording medium control section 8 for receiving output of the signalprocessing section 7 and controlling writing of the image datacompressed in JPEG, which will be hereinafter referred to as JPEG imagedata, and thumbnail image data into predetermined locations of arecording medium 9 or an expanded recording medium 10, read of therecorded JPEG image data therefrom, etc., the recording medium 9 andexpanded recording medium 10 for storing image data, an interface 11used to transfer data to and from an external system, display means 15of a LED lamp, etc., for displaying the switch state, functionalspecifications, etc., and display means 16 made of a liquid crystaldisplay, etc., for displaying a photographed image or an object to bepicked up.

The frame memory 6 normally is used as an image display memory of theliquid crystal display 16 and image data is expanded in bit map image.The frame memory 6′ normally is used as a menu display memory of theliquid crystal display 16. At the display time on the liquid crystaldisplay 16, the contents of the frame memories 6 and 6′ are superimposedon each other on the display.

The recording medium 9 is made of a 4-MB flash memory fixed in thecamera 100. It can be configured to record not only image data, but alsoprograms, etc. Compact flash (trademark of Sun Disk) having a capacityof 4-40 MB is used as the expanded recording medium 10 in theembodiment.

A serial interface is used as the interface 11 in the embodiment toreceive a program sent from a computer such as a PC 200, transmit imagedata to the PC 200, send image data via a modem 150 to a communicationline 160, etc., and transmit print image data to a printer 240 or afacsimile machine.

FIG. 1 b shows the configuration of the control section 4 which consistsof a CPU 41, a RAM 42, and a ROM 43. The ROM 43 stores control means 430made up of programs required for operation control of the digital camera100 and data processing in the digital camera such as data compressionprocessing (FIG. 2).

Print data preparation programs including a printer driver may be storedin the ROM 43. Alternatively, they can also be read from an externalrecording medium such as magnetic disk, CD-ROM, or a memory card intothe recording medium 9 or the expanded recording medium 10 and be readtherefrom for execution at a desired time.

FIG. 2 is a block diagram to show a configuration example of the controlmeans 430 stored in the ROM 43. The control means 430 consists of meansrequired for operation control of the digital camera 100, image dataprocessing means required in the process of storing image data such ascompression of image data, and means for decompressing compressed imagedata and preparing print data. Normally, the means are made of programs.

The control means 430 comprises a control system 431, input commanddetermination means 432, an internal program group 433, external programreception means 434, data management means 435, and display data outputmeans 436.

The control system 431 controls the whole operation of the digitalcamera 100, for example, an aperture motor drive section (not shown) inthe optical system, the operation of the signal processing section 3,the frame memory 6, the signal processing section 7, and the recordingmedium control section 8, and execution of the input commanddetermination means 432 to the display data output means 436.

When the user selects desired operation or processing by operating aswitch, etc., disposed on the digital camera 100, the input commanddetermination means 432 determines a digital signal output from theinput means 5 and determines what the user-entered command operation is.According to the determination result, the input command determinationmeans 432 transfers control to the corresponding program in the internalprogram group 433 or transfers control to the control system 431 for theexternal program reception means 434 to receive an external program.

The internal program group 433 consists of programs for controllingstorage of picked-up image data in the recording medium 9, read or writeof data from or into the expanded recording medium 10, LED display atthe image picking up time, etc.,; the programs are contained in the ROM43 as basic processing programs. For example, the internal programsinclude a JPEG compression program required for writing image data intothe recording medium 9.

The external program reception means 434 is started when the inputcommand determination means 432 outputs an external program introductioncommand.

The external program reception means 434 determines which of the PC orthe like, the expanded recording medium 10, and the communication line aprogram is to be introduced from by the contents of the external programintroduction command and performs corresponding reception processing,then transfers control to the data management means 435.

When picked-up image data is written into the recording medium 9,deleted, or added or program code introduced from the outside iswritten, deleted, or added, the data management means 435 performs datamanagement equivalent to file management widely performed in a computersuch as the PC.

The image data (data compressed in JPEG) and thumbnail image data areprocessed by the internal program 433 or its equivalent circuit and arewritten into the recording medium 9 by the recording medium controlsection 8.

The display data output means 436 outputs LED display data, image data,or display data of a menu, etc., to the LED display means 15 or theliquid crystal display 16 of the digital camera 100.

FIG. 3 is a block diagram to show a configuration example of imageselection means 45.

Image selection means 45A shown in FIG. 3 a comprises print imageselection means 453 for displaying picked-up image data on the liquidcrystal display 16 in order for the user to select a desired print imageand output method specification means 454 for specifying printspecifications of the number of print sheets, print paper size, printcolor mode (full color, single color, monochrome), etc., and an externalsystem to which the image data is to be transmitted. (See firstembodiment.)

Image selection means 45B shown in FIG. 3 b comprises thumbnail imagedisplay means 452 for displaying thumbnail image data on the liquidcrystal display 16 in a fast forward manner, print image selection means453′ for requesting the user to select a desired image from amongdisplayed thumbnail images and displaying the image data correspondingto the user-selected thumbnail image for the user to recognize it, andoutput method specification means 454 for specifying printspecifications and an external system to which the image data is to betransmitted. (See second embodiment.)

Image selection means 45C shown in FIG. 3 c comprises thumbnail imageprint means 452′ for adding index code to thumbnail image data andtransmitting to a printer for printing thumbnail images, print imageselection means 453″ for displaying a thumbnail image selection screenon the liquid crystal display 16 for the user to specify a desired imagebased on the printed thumbnail images and displaying the specified imagedata for the user to recognize it, and output method specification means454 for specifying print specifications and an external system to whichthe image data is to be transmitted. (See third embodiment.)

Image selection means 45D shown in FIG. 3 d comprises additional imageselection method specification means 451 for the user to select eitherthe image selection means 45B or 45C.

The image selection means 45A, 45B, 45C, or 45D may be introduced fromthe outside or can also be stored in the ROM 43 as one of the internalprograms 433 making up the control means 430 (FIG. 2). The output methodspecification means 454 has a setup value registration table comprisingsetup values and image index numbers provided in a one-to-onecorrespondence with each other.

FIG. 4 is a schematic representation to execute a direct print functionfor transmitting print image data to a printer, showing the relationshipamong the image selection means 45, the print image data preparationprogram group 50, and the control means 430. FIG. 5 is a flowchart toshow the operation of the control section 4 when the direct printfunction is executed.

In FIG. 4 and FIG. 5, when the user turns on an image selectionprocessing switch, the input command determination means 432 gives codemeaning image selection to the control system 431, which then reads theimage selection means (program) 45 from the ROM 43 or the recordingmedium 9 through the recording medium control section 8 at step P1.

When the image selection means 45 is expanded in the RAM 42, the controlsystem 431 transfers control to the image selection means 45. When theuser selects a desired image and specifies a desired output method, theimage selection means 45 goes to step P3 if the external system to whichimage data is to be transmitted is the printer 240 or a facsimilemachine. If the external system is the PC 200 or image data is sent tothe communication line through the modem 150, the image selection means45 goes to step P5 and transfers control to the control system 431 (P2).

The control system 431 gives an instruction for reading the print imagedata preparation program group 50 stored in the ROM 43 or the recordingmedium 9 through the recording medium control section 8. The programs(51, 52, 531, 532, 533, 54) in the print image data preparation programgroup 50 are read in the instruction order of the control system 431 andare expanded in the RAM 42 at step P3.

The control system 431 transfers control to the programs in the printimage data preparation program group 50 in order for preparing printimage data. At the termination of preparing the print image data at stepP4, control goes to step P5. The 1-frame image data can also be dividedinto several blocks in the subscanning direction for preparing the printimage data.

If the specified external system is the printer 240, the image datatransmission means 54 transmits print image data and print control datavia the interface 11 to the printer 240. If the specified externalsystem is a facsimile machine, the image data transmission means 54transmits monochrome print image data. If the external system is the PC200 or image data is sent to the communication line through the modem150, the image data transmission means 54 transmits image data or printimage data and print control data at step P5.

UV components of the image data (YUV component data) transferred to theprint image data preparation program group 50 are set to U=u and V=v(−1<u<1 and −1<v<1), whereby the image data output from the print imagedata preparation program group 50 can be made single-color (for example,sepia, blue, or green) image data. U=0 and V=0 are set, whereby theimage data output from the print image data preparation program group 50can be made monochrome image data.

The print image data preparation program group 50 contains a datadecompression program 51 for decompressing compressed data read from therecording medium 9, an RGB conversion program 52 for converting imagedata consisting of YUV components into RGB components, a printer driver53, and image data transmission program 54 for transmitting print data.

The printer driver 53 has the same configuration as a printer driver forpreparing print data in PC, etc., and comprises three modules ofrasterizer, color correction, and halftone to provide binary data.

Preferably, a color conversion parameter is added to the RGB conversionprogram 52 and a UV value conversion routine for setting U=0 and Y=0 atthe preceding stage of RGB conversion when the color conversionparameter is set to a given value (for example, ‘0, 0’) is added.

The image data transmission program 54 can also be configured totransmit print image data with the digital camera 100 connected to thecommunication line through the modem connected to the interface 11.Further, it can also be configured to transmit print image data bywireless with the digital camera lob connected to a radio unit such as aportable telephone through the modem connected to the interface 11.

FIG. 6 is a block diagram to show the configuration of the output methodspecification means 454. The output method specification means 454comprises output method specification screen display means 4541 fordisplaying an output method specification screen for specifying printspecifications and an external system to which image data is to betransmitted (FIG. 7 b), number-of-print-sheets specification means 4542for specifying the number of print sheets, print size specificationmeans 4543 for specifying a print paper size, print color modespecification means 4544 for specifying a print color mode, and outputunit specification means 4545 for specifying an external system to whichimage data is to be transmitted.

Preferably, the print size specification means 4543 comprises a table inwhich print paper sizes, such as A4, A6, and postcard or business cardsize, L format, and E format used with normal silver salt photos, arepreviously registered.

FIG. 7 shows an example of the rear part of the digital camera 100. Thedigital camera 100 is provided on the rear with the liquid crystaldisplay 16 for displaying an image or a function menu, etc., buttons 19and 20 for scrolling the screen of the liquid crystal display 16 up anddown and from side to side, and function selection buttons 17 and 18.FIG. 7 a provides an image display example and 7 b provides an outputmethod specification screen example.

Embodiment

Embodiments of image selection means 45 (45A, 45B, 45C, 45D) will bediscussed.

First Embodiment

FIG. 8 is a flowchart to show an operation example of image selectionmeans 45A. In the operation example, photographed image data pieces aredisplayed in order on a liquid crystal display and the user is requestedto select a desired print image and specify print specifications of thenumber of print sheets, print paper size, print color mode (color,single color, or monochrome), etc., then print image data is preparedand transmitted to an external system.

When the image selection means 45A is transferred to a RAM 42, a controlsystem 431 transfers control to the image selection means 45A. Printimage selection means 453 reads 1-frame image data, transfers the imagedata to a frame memory 6, uses a data decompression program to decomposeJPEG image data, and displays a candidate image 31 on a liquid crystaldisplay 16 at step S1. In this case, an index number is added to thecandidate image on the display.

If the user continues to press a button 19, the print image selectionmeans 453 displays candidate images in order. When the user releases thebutton, the print image selection means 453 stops the display at thecurrent image. If the user continues to press a button 20, the printimage selection means 453 displays the preceding candidate images inorder. When the user releases the button, the print image selectionmeans 453 stops the display at the current candidate image at step S2.

If the user presses either the button 17 or 18, the print imageselection means 453 assumes the candidate image to be selected andtransfers control to output method specification means 454 at step S3.

The output method specification means 454 displays an output methodspecification menu as shown in FIG. 7 b by output method specificationscreen display means 4541, prompting the user to select or enter theprint specifications and the external system to which image data is tobe transmitted.

At this time, initial display is, for example, “number of printsheets=1, print paper size=A4, print color mode=full color, outputunit=color printer.” The inside of a box 21 that can be specified orselected is displayed in a color different from the colors of otherboxes at step S4.

First, when the user presses the button 17 or 18, number-of-print-sheetsspecification means 4542 goes to a step for specifying the number ofprint sheets. Each time the user presses a button 19, the number ofprint sheets is incremented by one starting at the initial value and theresultant number of sheets is displayed. Each time the user presses abutton 20, the number of print sheets displayed is decremented by one.If the user presses either the button 17 or 18, the current displayvalue is set as the number of print sheets and is stored in the locationcorresponding to the image index number in a setup value registrationtable at step S5 and control goes to the next step.

When the user presses the button 17 or 18, print size specificationmeans 4543 goes to a step for selecting a print paper size and displaysthe contents of a print size registration table in which print papersizes are previously registered. If the user presses the button 19 or 20to select a desired print paper size and presses the button 17 or 18,the selected print paper size is set and is stored in the locationcorresponding to the image index number in the setup value registrationtable at step S6 and control goes to the next step.

When the user presses the button 17 or 18, print color modespecification means 4544 goes to a step for selecting a print color modeand displays the contents of a print color mode registration table inwhich print color modes are previously registered. If the user pressesthe button 19 or 20 to select a desired print color mode and presses thebutton 17 or 18, the selected print color mode is set. If full color isselected as the print color mode, a print color mode parameter in an RGBconversion program 52 is set to 1. If a single color is selected as theprint color mode, the print color mode parameter in the RGB conversionprogram 52 is set to 2. If monochrome is selected as the print colormode, the print color mode parameter in the RGB conversion program 52 isset to 3. The print color mode parameter is stored in the locationcorresponding to the image index number in the setup value registrationtable at step S7.

When the user presses the button 17 or 18, output unit specificationmeans 4545 goes to a step for selecting an output unit and displays thecontents of an output unit registration table in which output units arepreviously registered. If the user selects a color printer as the outputunit, an output unit parameter in an image data transmission program 54is set to 1. If the user selects a facsimile as the output unit, theoutput unit parameter in the image data transmission program 54 is setto 2. If the user selects a PC as the output unit, the output unitparameter in the image data transmission program 54 is set to 3. If theuser selects a communication terminal as the output unit, the outputunit parameter in the image data transmission program 54 is set to 4. Ifthe user presses the button 17 or 18, the selected output unit is setand the setup value corresponding to the selected output unit is storedin the location corresponding to the image index number in the setupvalue registration table, then control returns to step S1 to displayanother candidate image. If another candidate image does not exist, theoutput unit parameter value is checked. If the value is 1 or 2, controlgoes to step S9; if the value is 3 or 4, control goes to step S16.

The control system 431 expands programs contained in a print image datapreparation program group 50 in the RAM 42 in order and transferscontrol to a compressed data decompression program 51 at step S9.

The compressed data decompression program 51 reads image data (JPEGimage data) selected by the print image selection means 453 into the RAM42 and decompresses the data at step S10.

At the termination of decompressing the compressed image data, the RGBconversion program 52 checks the print color mode parameter at step S11.If the print color mode parameter has a value of 1, control goes to stepS12. If the print color mode parameter has a value of 2, all UVcomponents of the image data are converted into U=u and V=v. If theprint color mode parameter has a value of 3, all UV components of theimage data are converted into U=0 and V=0.

The RGB conversion program 52 converts the image data consisting of YUVcomponents into image data consisting of R (red), G (green), and B(blue) components at step S12. When the UV components are U=u and V=v,the image data is converted into single-color image data. When the UVcomponents are U=0 and V=0, the image data is converted into monochromeimage data.

A rasterizer 531 converts the image data into RGB continuous-tone (forexample, 256-gray-level) bit image data undergoing raster conversion foreach of R, G, and B at step S13.

A color correction module 532 applies color correction processing to theRGB continuous-tone bit image data to relate the data to print colorsand converts the data into CMYK continuous-tone bit image data for K(black), C (cyan), M (magenta), and Y (yellow) printing at step S14.

A halftone module 533 uses a dither method or an error diffusion methodto perform halftone processing for the CMYK continuous-tone bit imagedata at step S15, whereby a bit map binarized for each color (binarydata table) is prepared.

At the termination of the halftone processing, the image datatransmission program 54 checks the print color mode parameter. If thevalue of the print color mode parameter is 1, the image datatransmission program 54 transmits the setup values of the number ofprint sheets and the print paper size, a print control signal, andbinary bit map data to a color ink jet printer 240, for example, throughan interface 11 at step S16. The color ink jet printer 240 can receivethe print control signal and print data directly from the digital camera100 and print a desired number of sheets of the photographed image onrecording paper of a desired size.

If the user specifies a single color or monochrome as the print colormode, the image is printed in the single color or monochrome if it iscolor-photographed. If the value of the print color mode parameter is 2,the image data transmission program 54 transmits the setup values of thenumber of print sheets and the print paper size, a print control signal,and binary bit map data to a facsimile through an interface 11. If thevalue of the print color mode parameter is 3 or 4, the image datatransmission program 54 transmits JPEG image data or the setup values ofthe number of print sheets and the print paper size, a print controlsignal, and binary bit map data to PC 200 through the interface 11 or aterminal connected to a communication line 160 through a modem 150.

Second Embodiment

FIG. 9 is a flowchart to show an operation example of image selectionmeans 45B (FIG. 3B) wherein thumbnail images are displayed and the userselects a desired image and specifies print specifications of the numberof print sheets, print paper size, print color mode, etc., and an outputunit to which image data is to be transmitted.

When the image selection means 45B is transferred to a RAM 42, a controlsystem 431 transfers control to the image selection means 45B. Thumbnailimage display means 452 reads all thumbnail image data and expands thedata in the RAM 42 at step S21.

The thumbnail image display means 452 uses a data decompression programto decompose the thumbnail image data, enlarges the image data, adds anindex number to the enlarged thumbnail image data, and displays thethumbnail image on a liquid crystal display 16 at step S22. A number ofthumbnail images may be displayed on the liquid crystal display 16without enlarging the thumbnail image data.

Each time the user presses a button 19, print image selection means 453′displays one enlarged thumbnail image. If the user stops pressing thebutton 19, the print image selection means 453′ continues to display thecurrent thumbnail image. Each time the user presses a button 20, theprint image selection means 453′ displays the preceding thumbnail image.If the user stops pressing the button 20, the print image selectionmeans 453′ continues to display the current thumbnail image at step S23.

If the user stops pressing the button 19 or 20 and presses either thebutton 17 or 18 with the thumbnail image displayed, the print imageselection means 453′ assumes the image to be selected. When the userselects images from among the thumbnail images and completes selectionof desired images, the print image selection means 453′ transferscontrol to the control system 431.

The control system 431 transfers control to output method specificationmeans 454. At step S25, the output method specification means 454handles output method specification processing of print specifications,an output unit to which image data is to be transmitted, etc., andchecks the value of an output unit parameter at step S25. If theparameter value is 1 or 2, control goes to step S26; if the parametervalue 3 or 4, control goes to step S27.

The control system 431 expands print image data and programs containedin a print image data preparation program group 50 in the RAM 42 inorder and transfers control to the print image data preparation programgroup 50 at step S26.

The print image data preparation program group 50 performs similarprocessing to steps S10 to S15 in FIG. 8, namely, performs decompressionprocessing of image data (JPEG image data) selected by the print imageselection means 453′, RGB conversion processing, rasterizing, colorcorrection processing, and halftone processing at step S27.

At the termination of the halftone processing, as at step S16 in FIG. 8,an image data transmission program 54 checks the output unit parameterand transmits the print image data or JPEG image data to the specifiedoutput unit at step S28.

Third Embodiment

FIG. 10 is a flowchart to show an operation example of image selectionmeans 45C (FIG. 3 c) wherein thumbnail image data is printed at aprinter and the user selects a desired image from among the printedthumbnail images and specifies print specifications of the number ofprint sheets, print paper size, print color mode, etc., and an outputunit to which image data is to be transmitted.

A control system 431 expands programs contained in a print image datapreparation program group 50 in a RAM 42 in order and transfers controlto the image selection means 45C at step S31.

Thumbnail image print means 452′ reads all thumbnail image data, expandsthe image data in the RAM 42, decompresses the thumbnail image data inthe RAM 42, and adds an index number to each thumbnail image data pieceat step S32.

As described at steps S12 to S15 in FIG. 8, the print image datapreparation program group 50 performs RGB conversion processing,rasterize processing, color correction processing, and halftoneprocessing to prepare print thumbnail image data and transmits the imagedata to a printer 240 at step S33. In this case, the thumbnail imageprint means 452′ may set U and V components of the thumbnail image datain the RAM 42 to U=0 and V=0 to print a monochrome thumbnail image atthe printer 240.

Thumbnail images each with an index number are printed at the printer240 at step S34.

Print image selection means 453′ displays a message on a liquid crystaldisplay, prompting the user to select a desired image from among theprinted thumbnail images and enter the index number of the selectedimage at step S35.

If the user presses a button 19 as many times as the number of digits ofthe index number of the desired image and then presses a button 17 or18, the print image selection means 453″ reads the image datacorresponding to the index number from a recording medium 9 into a framememory 6 and displays the image on a liquid crystal display 16 at stepS36.

If the user furthermore presses the button 17 or 18, the print imageselection means 453″ assumes the image to be selected and transferscontrol to output method specification means 454 at step S37.

The output method specification means 454 handles setting of printspecifications and specification of an output unit to which image datais to be transmitted at step S38 as at steps S4 to S8 in FIG. 8. Toselect another candidate image, control returns to step S35. If anothercandidate image does not exist, the value of an output unit parameter ischecked. If the parameter value is 1 or 2, control goes to step S39; ifthe parameter value is 3 or 4, control goes to step S40.

The print image data preparation program group 50 performs decompressionprocessing of selected image data (JPEG image data), RGB conversionprocessing, rasterize processing, color correction processing, andhalftone processing at step S39 as at steps S10 to S15 in FIG. 8.

At the termination of the halftone processing, as at step S16 in FIG. 8,an image data transmission program 54 checks the output unit parameterand transmits the print image data or JPEG image data to the specifiedoutput unit at step, S40.

It is understood that the foregoing description is preferred embodimentsof the invention and that various changes and modifications may be madein the invention without departing from the spirit and scope thereof.

As described above, according to the invention, images are displayed ondisplay means such as a liquid crystal display of the digital camera andthe user selects a desired image from among the displayed images andspecifies the print specifications of the number of print sheets, aprint paper size, a print color mode, etc., then can transmit the printimage data prepared based on the user's selection and specification fromthe digital camera to a printer. Therefore, a photographed image can beprinted without intervention of another processing system such as a PCand it can be expected that digital cameras will come into wider use forthose who do not have a PC, etc., or who have a PC, but are unfamiliarwith handling the PC.

1. A digital camera, comprising: an image conversion device thatconverts a plurality of images into signals; a recording medium thatstores image data corresponding to the signals; a display that displaysat least one displayed image based on at least some of the stored imagedata; and an input device, wherein the at least one displayed image isselected to determine output image data when a user inputs a firstcommand via the input device, wherein the input of the first commandcauses the display to automatically display an output specificationscreen after the first command is input, and wherein the user can selectat least one predetermined output specification from the outputspecification screen via the input device.
 2. The digital cameraaccording to claim 1, wherein an external system processes the outputimage data based on the at least one predetermined output specification.3. The digital camera according to claim 2, wherein the digital cameradirectly outputs the output image data to the external system.
 4. Thedigital camera according to claim 1, wherein the first command is aselection command for selecting the at least one displayed imagedisplayed on the display as at least one selected image.
 5. The digitalcamera according to claim 4, wherein the at least one displayed imagecomprises at least one thumbnail image.
 6. The digital camera accordingto claim 5, wherein the at least one thumbnail image is displayed on thedisplay based on thumbnail image data stored in the recording medium tobe associated with the stored image data.
 7. The digital cameraaccording to claim 5, wherein two or more of the at least one thumbnailimage are sequentially displayed on the display before the user inputsthe first command.
 8. The digital camera according to claim 5, whereintwo or more of the at least one thumbnail image are simultaneouslydisplayed on the display before the user inputs the first command. 9.The digital camera of claim 4, wherein the user changes the at least onepredetermined output specification by inputting a second command via theinput device.
 10. The digital camera of claim 9, wherein the inputdevice comprises a scroll button, and wherein the user inputs the secondcommand by depressing the scroll button.
 11. The digital cameraaccording to claim 9, wherein the at least one predetermined outputspecification includes at least one of a number of print sheets and aprint paper size.
 12. The digital camera according to claim 1, wherein,when the output specification screen is initially displayed, at leastone initial output specification value for the at least onepredetermined output specification is displayed on the outputspecification screen.
 13. The digital camera according to claim 12,wherein the at least one initial output specification value includes aninitial value for at least one of the number of print sheets and thepaper size.
 14. The digital camera according to claim 1, wherein theinput device comprises at least one scroll button.
 15. The digitalcamera according to claim 14, wherein the at least one scroll buttonallows a user to change the at least one displayed image displayed onthe display.
 16. The digital camera according to claim 14, wherein theat least one scroll button allows a user to change at least one outputspecification contained in the output specification screen to select theat least one predetermined output specification.
 17. The digital cameraaccording to claim 15, wherein the at least one scroll button allows theuser to change at least one output specification contained in the outputspecification screen to select the at least one predetermined outputspecification.
 18. The digital camera according to claim 15, wherein theinput device further comprises at least one function button, wherein theat least one function button allows the user to select a displayed imagedisplayed on the display.
 19. The digital camera according to claim 16,wherein the input device further comprises at least one function button,wherein the at least one function button allows the user to select atleast one output specification contained in the output specificationscreen as the at least one predetermined output specification.
 20. Thedigital camera according to claim 17, wherein the input device furthercomprises at least one function button, wherein the at least onefunction button allows the user to select at least one outputspecification contained in the output specification screen as the atleast one predetermined output specification, and wherein the at leastone function button allows the user to select a displayed imagedisplayed on the display.
 21. The digital camera according to claim 1,wherein the input device includes a function button, wherein the userinputs the first command by depressing the function button under a firstpredetermined condition.
 22. The digital camera according to claim 21,wherein the first predetermined condition includes a condition in whicha desired image is currently displayed on the display as the at leastone displayed image.
 23. The digital camera according to claim 22,wherein the input device includes a scroll button, wherein the user canchange the at least one displayed image displayed on the display byinputting a second command via the scroll button before the firstcommand is input.
 24. The digital camera according to claim 23, wherein,when the output specification screen is initially displayed, at leastone initial output specification value for the at least onepredetermined output specification is displayed on the outputspecification screen, wherein the at least one initial outputspecification value displayed on the output specification screen ischanged only when the user inputs a third command via the scroll button.25. The digital camera according to claim 22, wherein the user sets atleast one output specification value, which is currently displayed onthe output specification screen, as the at least one predeterminedoutput specification by inputting a command via the function button. 26.The digital camera according to claim 24, wherein the user sets at leastone output specification value, which is currently displayed on theoutput specification screen, as the at least one predetermined outputspecification by inputting a command via the function button.
 27. Thedigital camera according to claim 1, wherein the at least onepredetermined output specification includes at least one of a number ofsheets and a paper size.
 28. The digital camera according to claim 1,wherein the at least one predetermined specification includes dataindicative of an external device to which the user desires to the outputimage data from the digital camera and that is selected by a user fromavailable external devices including at least two of a printer, afacsimile, a PC and a communication terminal.
 29. The digital cameraaccording to claim 28, wherein the communication terminal includes awireless telephone.
 30. The digital camera according to claim 1, furthercomprising conversion software contained in the digital camera, whereinthe conversion software formats the output image data to be output fromthe digital camera to an external system.
 31. The digital cameraaccording to claim 30, wherein the conversion software is supplied tothe digital camera from an external source and is installed in a memorycontained within the digital camera.
 32. The digital camera according toclaim 30, wherein the conversion software comprises a printer driver,and wherein the printer driver comprises at least one of a rasterizermodule, a half tone module, and a color correction module.
 33. Thedigital camera according to claim 1, wherein conversion software formatsthe output image data based on the at least one predetermined outputspecification.
 34. The digital camera according to claim 33, wherein theconversion software comprises a printer driver, and wherein the printerdriver comprises at least one of a rasterizer module, a half tonemodule, and a color correction module.
 35. The digital camera accordingto claim 1, wherein the digital camera comprises a wireless transmitterthat transmits the output image data to an external system by wirelesstransmission.
 36. The digital camera according to claim 35, wherein theexternal system is a wireless telephone.
 37. The digital cameraaccording to claim 1, wherein the stored image data includes higherresolution image data.
 38. The digital camera according to claim 37,wherein the stored image data further includes lower resolution imagedata associated with the higher resolution image data.
 39. The digitalcamera according to claim 38, wherein the lower resolution image dataincludes thumbnail image data.
 40. The digital camera according to claim37, wherein the at least one displayed image is displayed on the displaybased on the higher resolution image data.
 41. The digital cameraaccording to claim 39, wherein the at least one displayed image isdisplayed based on the thumbnail image data.
 42. The digital cameraaccording to claim 41, wherein the at least one displayed image isdisplayed based on the thumbnail image data by enlargement.
 43. Thedigital camera according to claim 37, wherein the output image dataincludes the higher resolution image data.
 44. The digital cameraaccording to claim 37, wherein the output image data includes dataobtained based on the higher resolution image data.
 45. The digitalcamera according to claim 39, wherein the output image data includes thethumbnail image data.
 46. The digital camera according to any one ofclaims 43 to 45, wherein the output image data further includes dataindicative of the at least one predetermined output specificationselected by the user.
 47. A digital camera, comprising: an imageconversion device that converts a plurality of images into signals; arecording medium that stores image data corresponding to the signals; adisplay that displays at least one displayed image based on at leastsome of the stored image data; and an input device having first andsecond buttons, wherein two or more of the at least one displayed imageare sequentially displayed on the display when the first button iscontinuously depressed; wherein an output specification screen for acurrently displayed one of the at least one displayed image is displayedon the display when the second button is depressed.
 48. The digitalcamera according to claim 47, wherein the currently displayed one of theat least one displayed image is selected to determine output image datawhen the second button is depressed.
 49. The digital camera according toclaim 47, wherein a user can select at least one predetermined outputspecification from the output specification screen.
 50. The digitalcamera according to claim 49, wherein the at least one predeterminedoutput specification includes a number of copies.
 51. The digital cameraaccording to claim 49, wherein the first button is used to change adisplayed value of an output specification in the output specificationscreen, and the second button is used to set a currently displayed valueof the output specification in the output specification screen as the atleast one predetermined output specification.
 52. A method of outputtingimage data from a digital camera including a display and an inputdevice, the method comprising: converting a plurality of images intosignals; storing image data corresponding to the signals; displaying atleast one displayed image on the display based on at least some of thestored image data; selecting the at least one displayed image todetermine output image data when a first command is input via the inputdevice; automatically displaying an output specification screen inresponse the first command; and selecting at least one predeterminedoutput specification from the output specification screen via the inputdevice.
 53. A method of outputting image data from a digital cameraincluding a display and an input device having first and second buttons,the method comprising: converting a plurality of images into signals;storing image data corresponding to the signals; displaying at least onedisplayed image on the display based on at least some of the storedimage data; sequentially displaying two or more of the at least onedisplayed image on the display when the first button is continuouslydepressed; and displaying an output specification screen for a currentlydisplayed one of the at least one displayed image on the display whenthe second button is depressed.
 54. The digital camera according toclaim 4, wherein at least two or more of the at least one displayedimage are sequentially displayed on the display before the user inputsthe first command.
 55. The digital camera according to claim 4, whereinat least two or more of the at least one displayed image aresimultaneously displayed on the display before the user inputs the firstcommand.
 56. The digital camera according to claim 1, wherein the outputimage data is directly transmitted to a printer when the specifying ofthe output specification, by a switch operation of the digital camera,is complete.
 57. The digital camera according to claim 1, wherein theoutput image data and the specified number of copies are directlytransmitted to a printer when the specifying of the print specification,by a button operation of the digital camera, is complete.
 58. Thedigital camera according to claim 47, wherein output image data isdirectly transmitted to a printer in response to completion of theoutput specification screen by a switch operation of the digital camera.59. The apparatus according to claim 47, wherein output image data and aspecified number of copies are directly transmitted to a printer inresponse to completion of the output specification screen by a buttonoperation of the digital camera.
 60. The method according to claim 52,wherein the output image data is directly transmitted to a printer whenthe selecting of the at least one predetermined output specification, bya switch operation of the digital camera, is complete.
 61. The methodaccording to claim 52, wherein the output image data and a specifiednumber of copies are directly transmitted to a printer when theselecting of the at least one predetermined output specification, by abutton operation of the digital camera, is complete.
 62. The methodaccording to claim 53, wherein output image data is directly transmittedto a printer in response to the completion of the output specificationscreen by a switch operation of the digital camera.
 63. The methodaccording to claim 53, wherein output image data and a specified numberof copies are directly transmitted to a printer in response to thecompletion of the output specification screen by a button operation ofthe digital camera.